1. Field of the Invention
The invention is directed generally to systems and methods for inhibiting corrosion, freezing, and other detrimental results caused by water within a cooling system of a liquid-cooled engine, and more particularly, to systems and methods for containing and delivering protective materials to raw water passageways of a cooling system in an open loop portion of a liquid-cooled marine engine.
2. Background
Combustion engines generate power by controlling multiple explosions of a combustible fuel. This process typically produces rotational motion and generates heat as a by-product, which is dissipated in various ways. Some engines dissipate the heat by-product using convection and air flow across fins and other surfaces. Other engines dissipate the excess heat generated through an exchanger using liquid, usually a water mixture. Specifically, water-based liquid is circulated through passageways located around the exterior portions of the engine proximate to the combustion chambers containing the pistons. Liquid-cooled combustion engines are typically either closed loop or open loop systems. Closed loop systems use recirculating liquids that are internally contained within the cooling system. The liquids used within a closed loop system absorbs heat generated by the engine and is cooled through a heat exchanger, such as a radiator. Open loop systems draw cooling liquids from an outside source, circulate it around the head of the engine and then discharge the heat laden water, normally back to the environment. Thus, only raw liquid is typically used within an open loop system.
Open loop liquid-cooled combustion engines are commonly used in the marine industries. Outboard engines, inboard/outboard engines, and inboard engines have all traditionally used liquid-cooled cooling system, and many marine engine designs have used open loop systems. In open loop systems, the engine draws raw water from the body of water in which the carrying vehicle is operating and circulates that raw water through the cooling system. As a result, engines cooled in such a way are subjected to water that includes contaminants and corrosive materials. For instance, when marine engines are operated in salt water marine environments, the engines circulate salt water through the cooling systems. As is well known, salt water is an extremely corrosive fluid that can severely limit engine life and efficiency.
There are also closed loop liquid-cooled marine engine designs, but they typically do not totally eliminate the risks associated with the open loop, raw water systems. These systems can be likened to those found in automobiles in which a water-based fluid is circulated through cooling channels in the combustion engine where heat is picked up, and then passed through the radiator where the heat is released to the relatively cooler air passing over the fins of the radiator. Where the marine version of the closed loop cooling design normally departs, however, is that instead of an air-exposed radiator, a heat exchanger is used which is exposed to a raw water, open loop conveyor or passageway. In this way, heat from the closed loop is transferred to the raw water at the heat exchanger. As described above, the raw water is then discharged back to the environment. Implementation of a closed loop design does not normally eliminate an open loop arrangement in a marine engine, but it does minimize and limit the exposure of the engine""s components to the corrosive raw water. That being said, even closed loop cooling arrangements on marine vessels will typically have an associated open loop system that is susceptible to the corrosive effects that raw water presents and which should be minimized through flushing procedures.
The corrosive nature of salt water has been traditionally addressed by using fresh water to flush the cooling system of a marine engine after is has been used in salt or brackish water. The conventional flushing process includes circulating fresh water through the cooling passageways of the liquid-cooled engine. This process is preferably performed soon after the engine has stopped running so that the salt water will be immediately removed from the cooling system, but especially before the water has evaporated leaving salt crystals on the inside surface of the passageways of the cooling system.
A conventional process for flushing outboard engines and inboard/outboard engines is to connect a fresh water source to the raw water intake ports located on the lower units of these marine power plants. The fresh water source can be a municipal water system, a well, or other system, and can be coupled to the raw water intake ports using a flush device that is commonly referred to as xe2x80x9cear muffsxe2x80x9d or xe2x80x9crabbit ears.xe2x80x9d The flush devices generally have a wishbone shape with form-fitting cups attached to each end of the arms of the device forming the wishbone shape of the device. The cups are made of a pliable material and are sized to cover the raw water intake ports on the lower unit. Typically, one of the cups is in fluid communication with a standard female garden hose fitting adapted to be connected to an end of a garden hose. During use, the cups are fitted over the raw water intake ports of the lower unit and a garden hose is connected to the device. The engine is flushed by first turning on the water and allowing the water to flow up to the raw water intake ports. The engine is started and allowed to run for a period of time normally ranging from about 5 to 7 minutes.
For engines equipped with thermostats within the cooling system, it is necessary to run the engine for a time period sufficient to allow the thermostat to open so that fresh water actively flows throughout the entire cooling system. Because the boat carrying the engine has often been trailered to a second location away from the body of water where it was operated, the engine is often beginning the flushing process in a xe2x80x9ccoldxe2x80x9d state. If so, short flushing periods will be inappropriate because in the beginning of the flushing process the fresh water only has the possibility of reaching essentially as far as the thermostat, with very little flushing water flowing therebeyond until the thermostat opens.
After a successful flushing period, the engine is stopped and the water flowing into the flushing device is then shut off. The flushing device is removed and the engine is assumed ready to be stored.
The flushing device described above is only suitable for use when the boat carrying the engine is out of the water. Otherwise, if this conventional flushing device is used while the boat remains in the water and, more importantly, while the lower unit of the power plant remains in the water, it is almost certain that corrosive raw water will seep into the raw water passages before, during and after the flushing process, thereby defeating the protective flushing measures.
While this flushing device circulates fresh water throughout the cooling system of a marine engine, it does not remove all of the salt water from the cooling system. Instead, there exist areas within most cooling systems that produce eddies when water is circulated through the engine. These eddies prevent some of the salt water from being removed from the cooling system. Thus, flushing an engine does not completely protect the open loop portion of a liquid-cooled marine engine from the corrosive action of salt water. Still further, there is no guarantee that the water used in the flushing process is itself absolutely pure and free of corrosive components.
Therefore, conventional flushing procedures at best partially protect a marine engine from salt water and also requires that the boat operator actively participate in the flushing process. Specifically, the operator must take the time to place the flush device on the lower unit and run the engine for the specified time period. While this preventive maintenance increases the life of a marine engine, many boat operators fail to flush their engine for any number of reasons such as lack of energy, lack of desire, or simply forgetting after along day on the water.
In addition to the fresh water flushing procedures described above, corrosion has been addressed by mixing anticorrosive fluids with the fresh water supply before the water enters the flushing device for added protection against corrosion. In one commercially available product, a canister containing an anticorrosive agent is coupled to a garden hose in line with the flushing device. As the water flows through the canister, a predetermined amount of the anticorrosive fluid is released into the fresh water flowing through the hose. This mixture containing the anticorrosive liquid is flushed through the cooling system as described above.
While the preceding discussion has primarily focused on flushing salt water from a marine engine, the cooling system of a liquid-cooled engine must also be properly prepared before being placed in storage for any extended period of time, and especially when being stored for the winter months in geographic locales subject to freezing temperatures. In such locales, it is necessary to winterize a marine engine. Winterizing a marine engine includes circulating an antifreeze material through the cooling system in order to prevent water contained in pockets within the cooling system from freezing and possibly causing significant damage to the cooling system and engine. This fluid can be circulated in some marine engines using the flushing device described above. Other engines require that the fluid be poured into the cooling system through strategically placed ports. This process can be time consuming and painstaking, especially when winterizing a marine engine that is housed within a tight engine room not allowing easy operator access.
Thus, a need exists for methods and arrangements for flushing an open loop portion of a liquid-cooled marine engine requiring less effort than is typically required by conventional systems. In addition, a system is needed that is more convenient by enabling an operator to flush an engine sitting either out of the water or in the water. Further, a system is needed that allows an engine to be protected when a pressurized source of fresh water is not available.
Set forth below is a brief summary of systems and methods configured and performed according to the present invention that address the foregoing problems and which provide benefits and advantages in accordance with the purposes of the invention as embodied and broadly described herein. According to one aspect, the invention is directed to a system for dispensing a protective material within passageways of a cooling system of a liquid-cooled engine. The system can be incorporated in different arrangements that include such liquid-cooled engines, many of which are mobile vehicles such as automobiles, trucks, airplanes and marine vessels. It should be appreciated, however, that the invention may be incorporated into other liquid-cooled engines that are not vehicle based. For instance, one example that is not directly vehicular in nature, but is at least marine-industry related, is a raw water cooled power generator on an off-shore drilling rig or platform. In most of the descriptions that are provided herein of the various embodiments of the invention(s), however, marine vehicles, such as power boats are contemplated as an appropriate and exemplary carrying vehicle.
The protective material can take the form of, or include substances or agents that are typically either in a liquid state or solid state, and have anticorrosive, antifreeze, biocidal and/or other beneficial properties. The system is sized to be incorporated at the engine, possibly in the engine compartment, or mounted on the carrying vessel in such a manner that does not require that the system or its components be removed during normal operation of the engine or boat. In addition, the system is designed to use protective materials that allow a marine engine to be flushed with raw water, which may contain corrosive contaminants such as salt. Thus, this system allows a marine engine to be protected from the corrosive action of raw water without having to flush the engine with fresh water. Instead, the engine can be xe2x80x9cflushedxe2x80x9d with salt or brackish water.
In one embodiment, the system includes a reservoir, a dispenser and a connection device. The reservoir contains the protective material and is sized to hold an amount of the protective material equal to at least one dose for the respective engine. Preferably, the amount contained within the reservoir equals multiple doses of the protective material. Release of the protective material contained within the reservoir is controlled by the dispenser. The dispenser may be of any number of designs, such as valves, clamps and other open/close devices. The dispenser can be manually operated or controlled remotely using an actuation device. The dispenser can be located within the reservoir, along a conduit connecting the reservoir and the cooling system of a liquid-cooled engine, or within the connection device connecting the system to the cooling system. The connection device couples the system to the cooling system of a liquid-cooled engine.
Another embodiment of the invention, includes the elements described above, together with an actuation device for controlling the release of the protective material from the reservoir. The actuation device can be controlled using a switch that may advantageously be mounted proximate to the ignition switch of the engine. Locating the switch controlling the actuation device in this position allows a boat operator to flush the engine without having to leave the console or driver""s position of the boat. Instead, the boat operator can control the operations for flushing the engine from the console where he or she will likely be conducting other shut down procedures.
In yet another embodiment of this invention, the system may include all of the elements described above and can further include a control unit for managing the release of the protective material. The control unit can provide many functions. For instance, the control unit can orchestrate the opening and closing of the dispenser. In addition, the control unit can stop the engine at the proper time during the flushing process. Further, the control unit can determine if the system is operating properly.
In another embodiment of this invention, the system can include all of those elements described above, but further includes additional elements. For instance, the system can include a gauge display for reading the amount of protective material contained within the reservoir. The gauge display can be mounted on the console or dashboard of the boat for easy viewing by the boat operator. In addition, the system can include a dispenser open indicator for signaling whether the dispenser is in an open position capable of releasing protective material. The system can also include an indicator device for signaling whether the protective material is flowing from the reservoir to the cooling system.
The system can be used with marine engines which include engine configurations such as those commonly referred to as outboard engines, inboard/outboard engines, and inboard engines. The system can be included in the original design of an engine and incorporated during the manufacturing and/or assembly process of the engine. In addition, the system can be sold as an aftermarket or retro-fit kit so that it can be included with an engine after the engine has been fully assembled, or even after installation of the engine on the carrying vessel.
This system can further include an injection pump incorporated within any of the embodiments described above. If the system includes a pressuring pump, the system can be coupled with the cooling system anywhere between the low-pressure raw water intake ports and the higher pressure portions of the cooling system after the water pump. Alternatively, if the system does not include an injection pump, the system can operate using a gravity feed system. If a gravity feed system is used, the system is coupled with the cooling system of the liquid-cooled engine downstream of the raw water intake ports and upstream of the water pump located within the engine where a vacuum normally exists.
This system can be used to flush a marine engine after it has been operated in fresh, salt or brackish water or to winterize an engine before it is placed in storage for an extended period of time. A method for using this system first includes determining whether the engine has an adequate source of water to cool the engine while it is running. As set forth above, this water can be fresh, salt or brackish water. The engine is then started if it is not already running and allowed to run until the engine reaches a normal operating temperature. Once the engine reaches this temperature, the thermostat opens, thereby opening the entire passageway of the cooling system. If the engine has already been running long enough for the thermostat to open, then the process described below can be implemented without delay.
The boat operator releases the treatment into the cooling system by actuating the dispenser manually or by using a switch or similar type input. The engine is allowed to continue running for a predetermined time period approximately corresponding to the amount of time required to circulate liquid from the raw water intake port(s), through the entire cooling system and on to the terminal end of the cooling system where the liquid exits the power plant. At the expiration of this time period, the engine is stopped at the direction of the user or the control unit. The dispenser is then closed to prevent additional release of protective material. Closing the dispenser can also be completed manually or at the direction of the control unit.
An advantage of this invention is that the system can flush a liquid-cooled marine engine using fresh, salt or brackish water. Thus, a boat operator can flush the engine immediately after operating the engine in salt or brackish water. This is advantageous for a number of reasons. For instance, it is important to flush an engine operated in brackish or salt water before the water within the cooling system evaporates and leaves salt deposits that corrode the passageways of the cooling system. In addition, by enabling a boat operator to flush the engine immediately after the boat has been docked, the boat operator is less likely to forget to flush the engine.
Another advantage of this invention is that the system can flush a liquid-cooled marine engine without a pressurized fresh water source, such as a municipal water source. Therefore, this system can be used to flush an engine while the boat rests in water anywhere. This is advantageous for any boat operator and especially those who use marine engines in harsh salt environments away from municipal utilities, and in other remote locations.
Yet another advantage of this invention is that flushing the engine with protective materials or agents provides the engine with greater protection than if the engine were flushed with water alone. Thus, this system offers greater engine protection with less effort than conventional systems.
Still another advantage of this invention is that it enables a boat operator to flush an engine with a system that is already installed. The boat operator is not required to install a flushing device to accomplish the flushing procedure, as is required to flush an engine using conventional systems. Thus, this invention makes flushing an engine easier and more effective than using conventional systems.